1. Field of the Invention
The invention relates to a device for improving the driving characteristics of a road vehicle which includes at least one upwardly projecting guide fin coupled to a control fin arranged on a pivotal axis.
2. Description of the Prior Art
The driving characteristics of road vehicles are determined on the one hand by wheels rolling in contact with the road, crawler tracks or sliding runners and their steering. On the other hand, aerodynamic forces act on the vehicle body while driving and possibly, in the case of open vehicles, on passengers and/or the load, which, in the form of air resistance, cause deceleration and, particularly in the case of a cross wind and/or turbulence, can disturb the driving characteristics. In order to reduce the deceleration effect, the superstructural components of road vehicles are streamlined, if possible, and designed with small cross-sectional areas. The center of the longitudinal sectional surfaces should be situated at or behind the center of gravity of the vehicle for reasons of stability.
In the case of open vehicles, such as motorcycles, attempts are made to reduce the deceleration effect and to improve the stability by means of fairings which deflect the air flow caused by movement of the vehicle partially around or over the passenger or passengers. In the case of two track vehicles, e.g. cars, it is known to arrange horizontal guide surfaces (spoilers) at the front and/or rear ends of the vehicles, which exert downward air forces on the vehicle and thus produce a larger ground pressure to transmit correspondingly larger frictional forces by virtue of an increased loading on the vehicle suspension.
Furthermore, devices of the type referred to above are known which e.g. include two vertical, fixedly arranged guide fins on the rear of the vehicle extending in the longitudinal direction of the vehicle. By virtue of such guide fins, air forces for improving the directional stability may be transmitted to the vehicle on the one hand but on the other hand, by virtue of the correspondingly increased longitudinal sectional area of the vehicle, its stability in the transverse direction, and thus the driving characteristics under the action of transverse forces, e.g. in the event of a cross wind, can be impaired.